What is a curb in roofing terminology?

In roofing terminology, a curb refers to a raised edge or frame that is often used to support structures like skylights, vents, or mechanical equipment on the roof. This raised structure typically elevates the object above the roof's surface, allowing for proper water drainage and preventing water from pooling around the base. The curb ensures that the installation is secure and helps maintain the integrity of the roofing system by diverting rainwater away from the point of entry. By providing this support, curbs are integral in extending the lifespan of the roofing elements and minimizing the risk of leaks.

In contrast, other options do not accurately define a curb in this context. A barrier to prevent water ingress suggests a different function typically associated with membranes or flashings. Roofing materials for insulation would refer to products like foam board or batt insulation, while decorative features would not typically be categorized as curbs, as they are more related to aesthetics rather than functional support structures.